The laryngeal mucocele. Imaging analysis of a rare lesion.

Four patients with laryngeal mucocele (fluid-filled laryngocele) are described. Two laryngeal mucoceles were external, lying outside the thyrohyoid membrane, and two were combined, lying both internal and external to the membrane. The combined laryngeal mucoceles presented with both neck mass and hoarseness. The external lesions and one combined lesion were diagnosed using computed tomography (CT) and ultrasound. Another combined lesion had the benefit of CT and magnetic resonance imaging (MRI) prior to exploration. All were homogeneously hypodense at CT with rim enhancement only in the case of the laryngopyocele. The mucocele evaluated with MRI had homogeneously long T1 and T2 relaxation times similar to cerebrospinal fluid.